Recessed vulva: An overlooked cause of chronic UTI in dogs

Photo 1A: The perineal region of a dog. Note that the vulva is not visible.

No doubt in your practice you’ve seen many urinary tract infections (UTIs). Dogs with UTIs can present with a history of frequent or inappropriate urination, accidents and a change in the color or odor of urine.

First-time, uncomplicated cases often are treated empirically with antibiotics. Many cases respond well, achieving resolution of the infection and clinical signs. However, dogs with recurrent infections require a more thorough evaluation.

The recommended diagnostic workup for recurrent UTIs should include complete physical examination, baseline blood work, urinalysis, urine culture and imaging with abdominal radiography, ultrasonography or both. Cystoscopy also can be useful in some patients. These tools provide the information needed to reach a definitive diagnosis, initiate appropriate treatment and resolve the UTI.

Photo 1B: The dog in Photo 1A after being shaved and prepped for surgery. Note the prominent dorsal vulvar skin fold completely covering the vulva.

Don’t overlook a recessed vulva

One commonly overlooked physical examination finding that may play a significant role in recurrent UTIs in female dogs is a recessed, or “hooded” vulva. Female dogs with a large skin fold effectively covering the vulva are highly susceptible to perivulvar dermatitis and recurrent UTIs. These dogs may also present with the complaint of incontinence. While perivulvar dermatitis may not be the only abnormality, it’s often a significant contributing factor and should be addressed.

Photo 1C: A preoperative photo of the dog in Photos 1A and 1B. The excessive skin is being held up to expose the vulva and to determine how much skin to remove.

The utility of an episioplasty

Episioplasty, the treatment of choice for dogs with excessive perivulvar skin folds, is a relatively simple procedure in which skin from between the anus and vulva is resected. The resulting wound is closed, and the previously hidden vulva is thereby exposed. See Photos 1A-1F and 2A-2C to see how two cases of recessed vulva were resolved.

Photo 1E: An intraoperative picture of the dog in Photos 1A-1D just before apposing the wound margins. The surgeon is checking to see if adequate skin has been removed to sufficiently expose the vulva.

The difficulty in this procedure is knowing how much skin to remove. Inadequate removal can result in continued dermatitis and UTIs and an unsatisfactory result (Photos 3A-3C). However, excessive skin removal can lead to tension on the surgical site and wound dehiscence.

Photo 3A: The perineum of a dog that had previously undergone an episioplasty with inadequate skin resection.

Additionally, there’s debate about when the procedure should be done. Many of these dogs present at younger than 1 year of age. Should you wait until maturity is reached? Will the dog outgrow its episioplasty?

In my opinion, episioplasty is indicated when excessive perivulvar skin fold is identified as a factor in a dog’s signs, regardless of the dog’s age.

Photo 3B: An intraoperative view of the dog in Photo 3A after skin resection, prior to wound closure.

Episioplasty should be effective long-term if adequate skin is removed, if there are no concurrent problems or they have been appropriately addressed and if the dog is maintained at a normal body weight. Resolution of the dermatitis, UTI and urine pooling via episioplasty may also result in improvement in previously noted incontinence.